1.8.1.1.2 DCLL TBM R&D Summary

1. 1.8.1.1.2 DCLL TBM R&D Summary Compiled by Neil Morley for the TBM Conference Call Oct 27, 2005

2. Main DCLL TBM R&D areas Are more tasks required for Engineering R&D??

3. Categorizing R&D Tasks • A system needs to be established to categorize R&D tasks to give a cost range. Suggestion: • E = Essential for the qualification and successful execution of the TBM experiment, and no other party is doing it • I = Important for the qualification and successful execution of the TBM experiment, or Essential but is definitely being done by another party • D = Desirable but the risk is acceptable if not performed • R&D subtasks should be categorized separately, if a task includes many subtasks. Costs need to be broken down by subtasks then, if not already done • Level 3 and 4 WBS coordinators should categorize tasks, as should R&D performers, to see if there is clear consensus on relative priorities. • Deadline for input ??

4. The following information is requested from each responsible person: • What critical need does this R&D address • Establish basic TBM feasibility • Understand/predict TBM performance • Design and fabricate first TBM – EM/S • Recommended scheduling of listed R&D tasks • Description of each task including: • Main purpose and method (numerical, experimental, …) • Identification of facility/code or description of new/upgraded facility/code required • Description of test section and diagnostics to be fabricated • Anticipated duration and person-years of effort • Any perceived overlap with another US R&D area and similar international R&D • Your categorization and justification

5. R&D Cost Estimate Summary (burdened, 2005 dollars, no contingency)

6. Schedule Summary

7. Modifications/Discussions since the last call

8. Tritium Permeation Issue and Originally Proposed R&D • Issue: Based on current analysis with conservative assumptions, annual tritium permeation to the ITER building appears be higher than projected allowable annual limit • Proposed Solution: aluminum or alumina coatings on exterior of PbLi and Helium pipes from TBM to transporter cask and from transporter cask to TCWS building. • Proposed R&D: measure tritium permeation from short pipe samples subjected to typical thermal cycling and coated with different materials and different coating techniques to quantify permeation reduce factors. Cost ~ $2.8M

9. 400 2.0 Helium piping 300 1.5 Tritium pressure above PbLi (Pa) Pb - 17Li piping Tritium release (mg-T/a) 200 1.0 ITER limit 0.5 100 Number of pulses 0.0 0 10 20 30 40 50 0 0 1000 2000 3000 Number of pulses High Performance TBM Tritium Permeation Results • TBM concentrations reach an oscillatory equilibrium after ~20 consecutive pulses, while helium pipe SS wall not reach an equilibrium after ~ 2000 consecutive pulses • Annual release based on 3000 consecutive pulses is 290 mg-T/a from helium pipes, and 180 mg-T/a from inlet PbLi pipe (total ~470 mg-T/a with limit of 100 mg-T/a); permeation barrier (alumina) or concentric pipe are required

10. Key points from tritium permeation conference call discussion • The following factors should greatly reduce the permeation • Inclusion of T removal from He coolant • More representative pulse sequences with longer down times • Optimization of the tritium permeator system (longer FS tubes or Nb/Ta tubes) • Natural oxide layers on steels • Off-normal factors might significantly increase permeation • Weld cracks, mistaken valve opening, other helium leaks, etc. • HCLL situation should be significantly worse due to high T partial pressure • More analysis of various cases needed • Testing in HH/DD phases to quantify permeation (and even mockups?) • New proposed solution if analysis and experience indicate a tritium permeation problem: • Swept secondary containment around transporter cask and TCWS skid for controlling leaked or permeated tritium • More aggressive permeator development to reduce tritium partial pressure in PbLi • Swept secondary containment around all PbLi (and He) piping • Operation at lower He/PbLi temperatures if limit is approached

11. Clarifications on the FCI Fabrication tasks • Irradiation experiments • do not include 18J doped samples, • All rabbit capsules to characterize property change and differential swelling of first generation recipe – timing is important to feed 2nd gen choices • 2nd irradiation is confirmatory on property changes of final FCI SiC/SiC recipe, could potentially be deferred several years

12. Clarifications on the FCI Fabrication tasks • Target electrical conductivity range is not critical for ITER testing • Sergey’s latest paper suggested that optimum FCI  of around 100 S/m for a DEMO application at the FW, but other effects, design variation and locations still must be analyzed. • Right now (for ITER testing) we can live with any transverse electrical conductivity (1-500 S/m) and transverse thermal conductivity (2-15 W/mK), but we do want to have a range to explore in testing • Structural integrity, thermal expansion, differential swelling in low dose irradiation, are also important

13. Thermofluid MHD Tasks TOTAL COST for 10-year: $12 M including hardware - Planning tests in ITER with supporting experiments and modeling; - Contribution to VTBM - R&D to support reference design - Development of modeling tools 900 K 900 K 900 K 900 K 400 K 250 K 250 K 200 K 300 K 300 K 300 K 200 K ? 200 K 200 K 200K 300 K 300k 300 K 300 K 200 K 200 K 300 K 400 K 300 K 200 K ? 200 K 200 K 200 K 200 K 200 K

14. Virtual TBM Schedule and Resources Cost Estimate $4.3M 1.5 man-yr/yr 1.5 man-yr/yr .5 man-yr/yr

15. Schedule and Budget for PbLi/SiC tasks Total = $0.75M